The project designs an intelligent directional following device based on ultrasonic positioning and strong robust PI controller. It locates and follows directly under the beacon’s guidance, which brings fast calculation, high positioning accuracy and sensitivity, low energy consumption, and easy control. New algorithm based on four receiving sensors also makes positioning more accurate. Using robust PI controller let it move much steadier and more adaptable to complex environments, with strong anti-interference ability. Its warning system ensures safety and no touching obstacles. Moreover, 3 highly reliable Omni-Wheels, 120° apart, make it move instantaneously in any direction. The device can be widely used indoors and has been granted two patents and won the National Gold Medal.